So, this won't go down in history as a sterling press conference. However, Biden does make it crystal clear that if war happens, it will be entirely of Putin's choosing. It's hard even for Russian TV to spin this as somehow belligerent. So there's that.

More seriously, Biden said three things:
1) The US sees no strategic logic in Putin's actions;
2) NATO is not itching for a fight;
3) Even if Putin 'goes small' & NATO doesn't move, the US is ready to hit back hard.
There's a logic to this approach, even if the delivery is off.

Given that Putin already knows (I hope) that no NATO member is going to get involved in a shooting war in Ukraine, and given ambiguity over his aims, effective deterrence requires a credible response across full range of potential Russian actions.

By contrast, claiming certainty and unity in the absence of either undermines deterrence, because it's not credible.